Clamp.



CHARLES A. DIES, 0F CHICAGO, ILLINOIS.

CLAMP.

Specification of Letters Patent.

Patented Mar. 26, 1913..

Application 'filed March 6, 191'?. Serial No. 152,476.

To all whom t 'may concern: Y Be it known. that I, CiiAnLns il. Drns, a citizen of the United States of America, and a resident of Chicago, in the county of Cook, State of Illinois, have invented certain new and useful Improvements in Clamps, of which the following is a specification.

This invention relates to that class of clamps in which the movements of a pair of clamping jaws are effected by an intermediate screw shaft, and their parallel relation maintained by an intermediate toggle link connection, And the present improvement has for its object, to provide a struc tural formation of parts wherein the parallel movement of the pair of jaws of a screw clamp are effected, and their parallel rela-` tion maintained in a simple and positive manner, and by means of which a light, strong and efficient tool is provided. All as will hereinafter more fully appear.

In the accompanying drawings Y Figure 1, is an elevation of the present clamp structure.

Fig. 2 is a transverse section on line -m, Fig. 1. l

Fig. 3, is an enlarged detail transverse section on line w-m, Fig. 1.

Similar reference numerals indicate like parts in the several views.

Referring to the drawing, 1, 2, designate a pair of counterpart clamp jaws of a straight rail form, and preferably of the U or chan nel shape shown in Figs. 2 and 3.

3 designates an operating screw-shaft journaled by a reduced shank portion l in an aforesaid jaw l, and provided with an enlarged operating head or handle 5, which in the construction shown, has bearing on a central transverse bridge piece 6 associated with said jaw l. The lower portion of the screw-shaft 3 has free movement in a central orifice in the companion clamp jaw 2, to thus provide a guiding connection between said parts.

7 designate a plurality of sliding heads of a U shape in cross-section, adapted to fit and slide upon the aforesaid jaws 1, 2, and provided with inturned hook shaped flanges 8 at the free ends of their side webs, for engagement with the corresponding free ends of the parallel side webs of said jaws 1 and 2, to hold the parts in proper sliding engagement after assemblage.

9 designate pairs of crossed or toggle links, disposed at opposite sides of the clamp jaws 1, 2, with the terminal ends of the links secured ina pivotal manner to the sliding heads 7 aforesaid, by pivot studs or tubular rivets 10, as shown.

11 designates a cross-head having a ccntral screw-threaded orifice for operative engagement with the screw-threaded portion of the operating screw-shaft 3 aforesaid, and'in addition, said cross-head 11 is provided with transversely projecting pivot studs 12 adapted for engagement in pivot orifices in the respective pairs of links 9 at the points where the links of each pair cross each other as shown.

13 designate contact or holding projections of a square or other suitable shape, arranged on the opposed faces of the clamp jaws 1, 2, near the ends thereof, and adapted for holding engagement with the work or material to which the clamp is applied.

The operation of the appliance is as follows With a turning movement of the operating screw shaft 3 in one or the other direction, a movement of the cross-head 11 is attained in a path at right angles to the parallel faces of the jaws 1, 2, and the jaw 2 is held from independent lateral movement in relation to the companion jaw 1 by the combined turning and sliding connection of the shaft 3 to the jaw 2. The central portions of the crossed links 9 being pivotally connected to the cross-head 11 have movement therewith, while the outer ends of said links 9 through their sliding engagement with the jaws 1, 2, have simultaneous movement upon said jaws and are adapted at all times to firmly brace said jaws in their proper parallel relation.

Having thus fully described my said invention, what I claim as new and desire to secure by Letters Patent, is

1. A clamp comprising, a pair of clamp jaws, an operating screw-shaft journaled centrally in one jawy and having central guiding connection. with the other jaw, pairs of crossed links disposed at opposite sides of said jaws, sliding heads arranged on said jaws and pivotally connected to the outer ends of the links aforesaid, and a central cross-head having screw-threaded engagement with the operating shaft aforesaid, and provided with transverse pivot studs having engagement with the aforesaid pairs of links at their crossing points, substantially as set forth.

2. A clamp comprising a pair of jaWs ofY a U' shape in cross-section, an operating screw-shaft journaled centrally in one jaw and having central guiding connection with the other jaw, pairs of crossed links disposed at opposite sides of said jaws, sliding heads of a U shape in cross-section and having hook shaped flanges at the ends of their side Webs, adapting said heads for sliding engagement with the elan'ip jaws, said sliding heads having pivotal connection with the outer ends of the links aforesaid, and a Central cross-head having a screw-threaded engagement with the operating shaft aforesaid, and provided with transverse pivot studs having engagement with theaforesaid pairs of links at their Crossing points, Vsubstantially as set forth.

8. A Clamp comprising a pair of jaws of a U shape in cross-section, a headed operating screw-shaft journaled Centrally in one jawv and having CentralV guiding VConnection with the other jaw, abridge plate on one jaw providing an abutment for th'elhea'd of said headed operatingscrew-shaft, pairs Vlinks aforesaid, and a Central cross-head having screw-threaded engagement with operating shaftY aforesaid, and provided with transverse pivot studs having engagement With the aforesaid pairs oflinks at their crossing points, substantially as set forth.V

Signed at Chicago, Illinois, this 23rd day of February, 1917. Y

CHARLES A. DrEs.

Colli?! of this patent may be obtained for five cents each, by addressing the Comniissoner of Patents, Washington, D. C. Y 

